The present invention relates to unloading mechanisms, and more particularly, to an unloading mechanism capable of automatically removing agricultural material from a storage bag.
Today, animal feed and other agricultural materials are often stored in elongated, tubular storage bags, rather than in traditional vertical silos and bunkers. Typically, these storage bags, because of their sizes, become considerably heavy and, therefore, virtually incapable of being lifted or otherwise moved when filled with agricultural materials. Therefore, bag contents must be removed from the bag, while it sits in its place, and deposited into a carrier capable of hauling the material to a destination at which the material is needed. As a consequence, bag-unloading machines of various constructs have been developed in the prior art. These machines typically have a frame assembly that features a mechanism(s) for engaging material inside a bag and removing it therefrom while the machine advances along the length of the stationary bag. Examples of such machines are disclosed in U.S. Pat. No. 6,109,552 to Strankman and U.S. Pat. No. 4,420,119 to Johnson.
Of course, all agricultural storage bags are not identical, and neither are all agricultural materials that these bags are used to hold. Consequently, the rate at which an unloading machine should travel down the length of a particular bag, as its material collection mechanism is engaging material therewithin and removing it therefrom, is dependent upon the rate at which the bag is actually being emptied. However, the bag emptying rate may vary, as it is dependent upon factors such as: the granularity of the agricultural material, the diameter of the storage bag and the collection and removal capacity of the machine's collection mechanism. Accordingly, while machines adapted specifically for unloading heavy agricultural storage bags are well-known in the prior art, the drive mechanisms that propel their frame assemblies along the length of a storage bag may require manual start and stop control during unloading operations, or they may need adjustment, from bag to bag, prior to operating at predetermined travel speeds.
Therefore, it can be appreciated that there remains a need for a bag unloading mechanism that is capable of sensing the rate at which material is being removed from a bag and then automatically advancing its frame assembly along the length of the bag and, therefore, its material collection mechanism further into the bag in a manner commensurate with that rate of material removal, so as to neither advance too slowly and, thereby, operate inefficiently nor advance too quickly and, thereby, overload and possibly jam the collection mechanism with material. The automatic unloading apparatus of the present invention substantially fulfills this outstanding need.